1. Field of the Invention
This invention relates to a printing equipment accessory, especially for making proof prints, with at least two rollers forming a roller nip through which is fed film from a supply roll, the film having a function component and an auxiliary component and the function component being transferable in the roller nip onto a base.
2. Description of Related Art
Such types of accessory apparatus are used, for example, to proof color separations. A composite film comprising a photopolymerizable layer between a support and a protective cover is taken from a supply roll as a first step. Before the film is passed into the roller nip, the protective cover is pulled off the polymerizable layer. The remainder of the film, the function component, is laminated on a base, for example, a paper sheet. The paper sheet with the photopolymerizable layer is exposed through an appropriate negative or positive, whereupon the exposed or unexposed areas, depending on composition, polymerize, whereas the remaining areas remain tacky. If necessary, the support layer muse still be removed. Color particles are now applied to the tacky areas. This can be done, for example, with a color transfer film having color particles on a support layer. This color film together with the exposed paper is passed through the roller nip. The pressure in the nip causes the color particles to adhere to the tacky areas and to separate from the color film when the color film is separated from the paper sheet. In this case, the color particles remaining on the paper sheet are the function component of the color film, whereas the support with the remaining color particles is the auxiliary component of the color film.
Other uses are laminating composite films or other coated materials, such as, for example, solder mask or dry film resist, on circuit boards to make printed circuits or to process hot melt adhesive films. In all of these uses, the auxiliary component, thus, for example, the protective cover or the support film with the remaining color particles, is waste that cannot be used for concurrent or subsequent proofing steps.
The auxiliary component of the film can be rewound to minimize the volume of this waste after being separated from the function component. For this purpose, an aid, for example, an adhesive band, attaches the beginning of the auxiliary component to a cardboard or synthetic resin core. This core can be, for example, the core from a used supply roll. Environmental protection dictates that not only must the waste volume be reduced, but it must be avoided. Therefore, attempts are made to reuse existing waste or to employ products that can be used many times, the so-called multiuse products.
To reuse the film's auxiliary component, it must be separated from the core to obtain an unblemished product. The auxiliary component of the film can be unwound from the core; this consumes time and work. Therefore, the film roll is usually cut off and the core removed. However, this generates film slivers and additional contamination. It also increases the volume of waste. The necessary added work increases the setup time and incurs needless expense. The core is usually damaged during cutting and therefor cannot be reused in the multiuse system.